statsmodels.robust.norms.AndrewWave.rho

AndrewWave.rho(z)

The robust criterion function for Andrew’s wave.

Parameters:z (array-like) – 1d array Returns:rho – rho(z) = a*(1-cos(z/a)) for |z| <= a*pi

rho(z) = 2*a for |z| > a*pi

Return type:array